The biennial Gordon Research Conference (GRC) and Gordon Research Seminar (GRS) on the Cell Biology of Megakaryocytes and Platelets brings together current leaders, junior investigators and trainees working on the development and disorders of the megakaryocyte lineage. It is the premier international meeting in the field. The ongoing, long-term scientific mission is to bridge the gap between researchers working on different aspects of the lineage, i.e. stem cells, megakaryocytes and platelets. This mission is more relevant than ever, as the interdependence between each cell type becomes increasingly clear, e.g. the role of megakaryocytes in stem cell development, and the impact of inflammation on megakaryocyte growth and platelet production. The overarching, aim of the GRC is to allow current and emerging leaders of the field to communicate unpublished data, thereby educating colleagues, promoting discussions and fostering collaborations. The aims are to: 1. Highlight the extraordinary progress being made in our understanding of platelet function in the context of hemostasis, thrombosis, and inherited/ congenital platelet disorders. Talks will cover the state-of-the-art on platelet surface receptor function and intracellular signaling, the development of new targets for antiplatelet therapy, and the immense progress made in diagnosing and treating platelet function disorders. 2. Discuss the latest unpublished research on the engineering of in vitro generated platelets and platelet-like nanoparticles. These cutting-edge approaches hold the promise to revolutionize the way we obtain platelets for transfusion purposes, including designer platelets that are optimized for the use in individual patients. 3. Link the lineage to immunity and inflammation. It is increasingly apparent that platelets can promote inflammation, and that inflammation and infection can affect thrombopoiesis. In a dedicated session, we will discuss this unique interplay between the megakaryocyte lineage and the immune system. 4. Redefine the lineage and the bone marrow niche. Two sessions discuss the latest findings on lineage development and composition of the bone marrow niche, both under steady state and pathologic conditions. 5. Discuss studies that push the field into new directions, including updates on the lung as a major organ for thrombopoiesis, platelets as migrating immune cells, and new technologies to study these cells on a single cell level. To optimize interaction between researchers, we have designed most sessions so that they feature talks on both platelets and megakaryocytes. We also decided to continue with a new format that was implemented in 2017, i.e. the incorporation of 12 talks to be selected from abstracts within the main sessions (eliminating a dedicated hot topics session). Multidisciplinarity will be emphasized throughout the whole meeting, and both basic science and translational aspects of the field will be discussed.